More of a fix than a custom; I was at Target just mucking about and saw the Punisher/Iron Man 2-pack. I've really been wanting a Punisher but the head sculpt is just atrocious. Luckily, on the peg above it, there was a DC Universe Black Adam on clearance for $2.50, which sports a head that, barring the pointy ears, looked dead like Frank Castle.
So I brought 'em home, chopped the ears, repainted the hair a little better, repainted the neck and sealed it (but apparently missed a spot I didn't see till the pics), and popped the new head on. Instant Frank Castle!